
\begin{tikzpicture}[scale=.4]
  \draw (-8,-8) rectangle (8,8) (-8,0) -- (8,0) (0,-8) -- (0,8)
    (-8,-8) -- node[above] {$2^{n - 1}$} (0,-8);
  \draw[opafill=cyan]
    (0,0) rectangle (-1,1)  (0,0) rectangle (1,-1)
    (0,0) rectangle (-1,-1) (4,5) rectangle (5,6);
  \node at (-.5, .5) {$S_1$};
  \node at ( .5,-.5) {$S_2$};
  \node at (-.5,-.5) {$S_3$};
  \node at (4.5,5.5) { $S$ };
\end{tikzpicture}
